Electroplating racks



May 1, 1962 w. E. BELKE ELECTROPLATING RACKS Original Filed May 26, 1955 IN VEN TOR. d fiefle @4/ MJM The present invention relates to electroplating racks,

and is particularly concerned with the provision of improved structures for meeting the electroplating requirements of an infinite number of different articles.

The present application is a division of my prior'application, Ser. No. 686,616, 'filed September 27, 1957, now patent No. 2,958,642, on Plating Racks; which in turn is a division of my prior application, Ser. No. 511,264, filed May 26, 1955, now patent No. 2,820,757; on Plating Racks. I

One of the objects of the invention is the provision of an improved plating rack assembly of a rugged type in which the parts are so assembled with a supporting spine that a low resistance electrical connection is assured between the rack parts by cutting into the metal of one part with'the other and exposing a bright new surface, for effecting the electrical connection each time the parts are assembled.

Another object of the invention is the provision of an improved electroplating rack of the class described in which provision is made for automatically covering and sealing the clean connecting surfaces against the ingress of electrolyte for maintaining good electrical connection and preventing erosion of the conducting metal.

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings, in which similar characters of reference indicate similar parts throughout the several views.

Referring to the single sheet of drawings accompanying this specification,

FIG. 1 is a view in perspective of an electroplating rack assembly with various exemplary plating tips;

FIG. 2 is a sectional view taken on the plane of the line 2-2 of FIG. 1, looking in the direction of the arrows;

FIG. 3 is a view in perspective of a securing clip which is an important part of the rack assembly;

FIG. 4 is an enlarged side elevational view of a connector bushing which supports the plating tip on the spine;

FIG. 5 is a similar view of another form of bushing.

Referring to FIG. 1, this is a view in perspective which is exemplary of an infinite number of rack assemblies which may be made up out of one or more spine members 20 and one or more tip members 21, 22, 23, or 24.

The present invention relates particularly to the tip assembly indicated at 23.

All of the tip members and racks have in common the fact that they are coated with an initially plastic layer of electric insulation 25 covering every part of the rack and tips, which are immersed in the electrolyte or subjected to its fumes, excepting the upper V-shaped hook 26 of the rack 20, which hook is electrically connected to the conducting rod on which it is supported, and excepting the extreme end surfaces 27 of the tips on that side where the tips engage the electroplated articles.

The rack member 20, also called a spine, comprises an elongated metal bar of substantial thickness and width of conducting metal, such as copper, provided with a hook 26 at one end and with the insulating coating 25, and having a plurality of cylindrical apertures 28 extending through the coating and copper for attachment of the various types-of tips.

For example, the tip 23 is a rugged fiat spring tip including a pairof relatively flat copper springs 61 and 62, the central bodies of which are provided with registering apertures 63.

The bodies of the springs 61, 62 are riveted together at 64, 64, and formed with the outwardly turned obtuse angles 65 so that their end portions 66 diverge.

The bodies of the springs 61, 62 are secured to a cutting bushing 46 by means of a clip 47 of the type shown in FIG. 3. A headed screw bolt 48 has its threaded shank 49 passing through the aperture 63 in the springs 61, 62; and the shank 49 is threaded into the threaded bore 50 in the bushing'46.

A clip 47 is interposed between the springs 61, 62 and the hexagonal head 51 of the bushing 46; and the shank 49 passes through'the aperture 52 in the clip.

The clip 47 has a rectangular body 53 and a pair of backwardly turned flanges 54 extending at right angles to the body and spaced from each other sufficiently to engage the'flat sides of the head 51 on the bushing 46.

Two additional flanges 55 are carried by the top and bottom of the clip 47 and extend backwardly at right angles, being spaced from each other sufiiciently to engage above and below the springs 61, 62. Thus the clip prevents relative rotation between the bushing 46 and the springs 61, 62 when the screw bolt 48 is drawn up.

Instead of the bushing 46, an equivalent type of bushing 56, shown in FIG. 4, may be employed, having a threaded portion 57 extending from its head, which may receive a nut performing the same function as the screw bolt 48.

The bushings 46 or 56 are each provided with a tapered frusto-conical surface 58, which is formed with a multiplicity of sharp cutting teeth or ridges 59 separated by grooves 60.

The threaded bore 50 in the bushing engages a threaded bolt 70, which has no head, but is provided with a screwdriver slot at its outer end.

The bolt 70 is provided with a threaded non-circular nut 72 having a frusto-conical end 73 and a threaded bore 74; and the nut 72 is adapted to draw the bolt 70 and the clip toward the spine. In so doing the bolt 70 draws the sharp edges of the bushing into cutting engagement with the aperture 28 of the spine, producing new, bright electrically conducting surfaces between the tip assembly and the spine.

The insulating coating 25 on the tip assembly is provided with a cup shaped resilient formation 75 which presses tightly against the insulation on the spine and effects a liquid-tight seal, preventing the electrolyte from reaching the bushing or other parts.

The exposed end of the bolt is provided with an insulating cap 76 having a threaded bore 77 engaging the end of the bolt and having an enlarged bore 78 surrounding and covering the nut 72.

The insulating nut 76 has its outer end drawn tightly against the insulation at 79, effecting a liquid-tight seal against the entry of the electrolyte at this side of the spine.

It will thus be observed that the rack assembly provides automatically for an acid-tight seal surrounding and enclosing the newly cut and bright engaging surfaces between the parts of the tip and the parts of the supporting spine.

While I have illustrated a preferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish to be limited to the precise details of construction set forth, but desire to avail myself of all changeswithin the scope of the appended claim.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:

An electroplating rack comprising an elongated vertically extending metal spine having a flat body formed at its upper end with a downwardly open V-shaped hook, said body being covered over all except at its hook with an initially plastic layer of electric insulation, the said body being provided witha plurality of transversely extending apertures spaced from each other, and each aperture being provided with a top structure for supporting articles to be electroplated, one of said apertures being provided with an electrically conducting bushing having a tapered end and a threaded bore, the said tapered end being longitudinally grooved and provided with converging sharp edges bordering its grooves and adapted to cut a new bright contacting surface in the aperture in said body when the tapered end is forced into said aperture, a thredaed shank in the bore of said bushing and extending from the bushing and through the aperture of said body and projecting from the other side of said body, an elongated noncircular nut having a threaded bore receiving the said shank on which it is threaded, and said nut having a frusto-conical end engaging the adjacent side-of said body'andcenteringsaid shank in said aperture, the said nut drawing the nut and the bushing into said apertureto eflect a tight electrical connection, said shank projecting beyond said nut with its threaded end, and having an insulatingcover nut provided with a threaded bore for receiving the threaded end of the shank and having a counterbore large enough to rotate about said tapered nut, the said cover nut engaging the plastic insulation on said body and excluding electrolyte from engagement with the tapered nut and threaded shank at that side of the body, a threaded bolt having a noncircular head threaded in said bushing, and a heavy duty tip assembly having an aperture receiving said bolt, which extends through said aperture to secure said tip assembly to said bushing, said tip assembly comprising a square plate having a pair of right angle flanges extending toward said spine and located on the opposite sides of said bushing and engaging non-circular surfaces on said bushing, said square plate having an aperture for said bolt and having another pair of outwardly projecting right angle flanges engaging the edges of said tip assembly, the said tip assembly comprising a pair of relatively heavy flat springs riveted together at a central body portion which has an aperture receiving said bolt, the said springs being bent outwardly at each end of said body portion to form four diagonally outwardly extending arms for supporting articles to'be electroplated, the said tip assembly and bolt and exposed portions of the bushing being covered overall with electric insulation having a cup shaped formation 'around'the bushing engaging the insulation on the spine and excluding electrolyte on that side of the spine.

References Cited in the file of this patent Metal Finishing, January 1950, page 19. Belke Plating- Rack Manual (1947), plate 40. 

